Do The Twist: Efficient Heavy-Atom-Free Visible Light Polymerization Facilitated by Spin-Orbit Charge Transfer Inter-system Crossing.
Angew Chem Int Ed Engl
; 62(22): e202219140, 2023 May 22.
Article
en En
| MEDLINE
| ID: mdl-36988076
ABSTRACT
The use of visible light to drive polymerizations with spatiotemporal control offers a mild alternative to contemporary UV-light-based production of soft materials. In this spectral region, photoredox catalysis represents the most efficient polymerization method, yet it relies on the use of heavy-atoms, such as precious metals or toxic halogens. Herein, spin-orbit charge transfer intersystem crossing from boron dipyrromethene (BODIPY) dyads bearing twisted aromatic groups is shown to enable efficient visible light polymerizations in the absence of heavy-atoms. A ≈5-15× increase in polymerization rate and improved photostability was achieved for twisted BODIPYs relative to controls. Furthermore, monomer polarity had a distinct effect on polymerization rate, which was attributed to charge transfer stabilization based on ultrafast transient absorption and phosphorescence spectroscopies. Finally, rapid and high-resolution 3D printing with a green LED was demonstrated using the present photosystem.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Año:
2023
Tipo del documento:
Article
País de afiliación:
Estados Unidos